FACIES CHANGES AND TRANSVERSE CORRELATION OF THE SINIAN—CAMBRIAN BOUNDARY STRATA IN EASTERN YUNNAN

This paper deals with the division and transverse correlation of the Sinian-Cambrian boundary strata between the phosphate-carbonate sedimentary facies region and phosphorus-bearing carbonate sedimentary region in eastern Yunnan on the basis of the subdivision, correlation and facies analysis of three representative stratigraphic sections at the Sinian—Cambrian boundary,i.e. Dahai section in Huize County, Ershao section in Luquan County and Sapushan section in Wuding County. From east to west, the phosphorite facies grades into the phosphorus-bearing carbonate rock facies in the Zhongyicun member, and in the Xiaowaitoushan member, the siliceous rock facies passes into the siliceous dolostone facies. The positions of facies changes are roughly controlled by N—S-trending Pudu River palaeofault.